Drug packaging apparatuses that automatically dispense a plurality of units of a drug (the units hereinafter meaning tablets, capsules, pills, lozenges, and any other discrete forms of a drug that can be individually handled, and the units of a drug hereinafter being referred to as simply drug units) as prescribed for a variety of illnesses and package the drug units in single doses have recently become widely available. The drug packaging apparatuses are required to dispense and package a drug unit by unit.
Such a drug packaging apparatus is equipped with a supply apparatus that guides drug units discharged from a drug storage tank to drug packaging members. However, when drug units that are sequentially discharged, unit by unit, from a drug storage tank are supplied to drug packaging members through the supply apparatus, the drug units time-divisionally discharged from the drug storage tank are likely to be supplied to the same drug packing member. Alternatively, the drug units are likely to congest a supply path of the supply apparatus, resulting in the drug units staying in the supply apparatus. That is, drug dispensing errors occur when drug units are conveyed to drug packaging members through the supply apparatus.